Operating Revenues – Unigas Pool. Operating revenues – Unigas Pool was $13.5 million for the three months ended March 31, 2022 and represents our share of the revenues earned from our nine vessels (following the sale of the Happy Bird on March 7, 2022) operating within the Unigas Pool, based on agreed pool points. These vessels were acquired as part of the Ultragas Transaction in August 2021, and therefore there are no Operating Revenues—Unigas Pool for the three months ended March 31, 2021.
Operating Revenues – Luna Pool Collaborative Arrangements. Pool earnings are aggregated and then allocated (after deducting pool overheads and managers fees) to the Pool Participants in accordance with the Pooling Agreement. Operating revenues—Luna Pool collaborative arrangements was $5.9 million for the three months ended March 31, 2022, compared to $5.2 million for the three months ended March 31, 2021 and represents our share of pool net revenues generated by the other participant’s vessels in the pool. The Luna Pool, which comprises nine of the Company’s ethylene vessels and five ethylene vessels from Pacific Gas Pte. Ltd., focuses on the transportation of ethylene and ethane to meet the growing demands of our customers.
Brokerage Commissions. Brokerage commissions, which typically vary between 1.25% and 2.5% of operating revenues, increased by $0.2 million or 17.9% to $1.4 million for the three months ended March 31, 2022, from $1.2 million for the three months ended March 31, 2021, primarily due to an increase in operating revenues on which brokerage commissions are based.
Voyage Expenses. Voyage expenses increased by $5.2 million or 33.2% to $20.8 million for the three months ended March 31, 2022, from $15.6 million for the three months ended March 31, 2021. This increase is primarily due to voyage expenses of the additional seven handysize vessels acquired as part of the Ultragas Transaction. These voyage expenses are pass through costs, corresponding to an increase in operating revenues of the same amount.
Voyage Expenses – Luna Pool Collaborative Arrangements. Voyage expenses – Luna Pool collaborative arrangements were $4.6 million for the three months ended March 31, 2022, compared to $4.1 million for the three months ended March 31, 2021. These voyages expenses – Luna Pool collaborative arrangements represent the other participant’s share of pool net revenues generated by our vessels in the pool. The net effect after deducting operating revenues – Luna Pool collaborative arrangements was that the other participant’s vessels contributed $1.3 million to our vessels in the Luna Pool for the three months ended March 31, 2022, compared to the other participant’s vessels contributing $1.1 million to our vessels for the three months ended March 31, 2021.
Vessel Operating Expenses. Vessel operating expenses increased by $11.1 million or 41.0% to $38.1 million for the three months ended March 31, 2022, from $27.0 million for the three months ended March 31, 2021, primarily as a result of the additional Ultragas vessels joining the fleet. Average daily vessel operating expenses decreased by $51 per vessel per day, or 0.6%, to $7,841 per vessel per day for the three months ended March 31, 2022, compared to $7,892 per vessel per day for the three months ended March 31, 2021.
Depreciation and Amortization. Depreciation and amortization increased by $12.2 million or 63.2% to $31.5 million for the three months ended March 31, 2022, from $19.3 million for the three months ended March 31, 2021. Of this increase, $5.9 million results from the additional 16 vessels in the fleet, acquired as part of the Ultragas Transaction and $6.1 million results from the change in the useful economic lives of the vessels in the fleet from 30 years to 25 years. Depreciation and amortization included amortization of capitalized drydocking costs of $3.7 million and $2.2 million for the three months ended March 31, 2022 and 2021 respectively.
Profit from Sale of Vessel. Profit from sale of vessel for the three months ended March 31, 2022 was $0.5 million and related to the sale of the vessel Happy Bird. The sale of Navigator Neptune was at book value, therefore there was no profit or loss on the sale of this vessel.
General and Administrative Costs. General and administrative costs increased slightly by $0.1 million or 1.0% to $6.3 million for the three months ended March 31, 2022, from $6.3 million for the three months ended March 31, 2021, primarily as a result of the additional general and administrative costs of Ultragas of $1.2 million, off-set by a reallocation of technical management costs to vessel operating expenses of $0.7 million and a reduction of other costs of $0.3 million including cost reductions associated with the closure of our New York office.
Other Income. Other income was $0.1 million for both the three months ended March 31, 2022 and 2021 and consists of that portion of the management fees for commercial and administrative activities performed by the Company for the Luna Pool, relating to the other participant’s vessels.
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